Shot hole pole and coupling



Ndv. 25, 1958 R. E. MCMACKIN ET AL 2,861,823

snow nous POLE'AND COUPLING Filed July 27. 1953 INVENTORS ATTORNEY United States Patent SHOT HOLE POLE AND COUPLING Robert E. McMackin and Edwin E. McMackin,

Dallas, Tex.

Application July 27, 1953, Serial No. 370,337

Claims. (Cl. 287-103) This invention relates to loading poles for lowering charges into shot holes in geophysical prospecting and more particularly to ,new and useful improvements in couplings for loading pole sections. 7 i

In geophysical prospecting, shot holes are bored in the earth within a geologically promising area and charges of dynamite are lowered into the shot holes and subsequently detonated by electrical current supplied from the surface through wires lowered with the charges, the shock waves generated by the explosions being recorded on seis-' mographic charts.

The principal object of the invention is to provide a loading pole and coupling for conveniently and safely lowering dynamite charges into shot holes and to preclude premature detonation.

Another object of the invention is to provide a coupling consisting of'complementary members, one on each end of a pole section and engageable with corresponding members on the ends of adjacent pole sections only by rotation of a pole section 90 to dispose its longitudinal axis at right angles to the axis of a companion pole section to properly align the coupling members for relative engagement and disengagement.

Still another object of the invention is to provide a loading pole section made preferably of plastic or other material of equal lightness and rigidity and a coupling member having a shank portion receivable in each end of the pole section and in sealing engagement therewith to insure against infiltration of Water and other foreign matter which would increase the Weight of the loading pole, a condition to be avoided since the pole is lowered into and withdrawn from the shot hole.

Other objects will appear as the description proceeds, when considered with the annexed drawing, wherein:-

Figure l is a vertical sectional view through a shot hole showing a string of loading pole sections coupled together according to the invention. 1

Figure 2 is a view on a larger scale showing a pole section in longitudinal section, with a coupling member in each end thereof.

Figure 3 is a fragmentary elevational view of a male coupling member.

Figure 4 is a view in transverse section, taken on' line 4-4 of Figure 2.

Figure 5 is a view in transverse section, taken on line 5-5 of Figure 2.

Figure 6 is a fragmentary elevational view of a female coupling member, and

Figure 7 shows a modified example of the invention with parts in section.

Referring to the drawing, numeral 10 denotes a tubular member of plastic or other light and durable material, constituting a section of the loading pole and is preferably ten feet in length for easy handling and storage but it can be of any length desired.

The pole sections 10 are joined together at their ends as they are lowered into the shot hole 11, which shot holes range from a few feet to some three hundred feet,

2,861,828 Patented Nov. 25, 1958 more or less, in depth. To avoid any likelihood of separation, the sections 10 are connected one to another by the male and female coupling members 12 and 13, respectively. The coupling member 12 consists of an annular head 14 on which is formed a hook 15. The hook 15 forms-an incomplete circle, the opening 16 being disposed at right angles to the longitudinal axis of a shank 17 formed on the head 14 opposite the hook 15.

The coupling member 12 is preferably cast in a single piece, the shank 17 being received in one end of the pole section 10 and secured therein by a transverse pin 18 which extends through a cylindrical end portion 19 of the shank and through the walls of the tubular pole section 10.

That portion of the shank 17 intermediate the end 19 and head 14 is lightened in weight by being formed of a series of tapered ribs 20, originating at the longitudinal axis of the shank and extending radially outward to the same circumference as the cylindrical end portion 19 and a shoulder 21 formed at the opposite end of the shank.

. The diameter of the shoulder 21, end portion 19 and ribs 20 is such as to provide a close frictional fit of the shank within the end of the pole section 10 and by means of a suitable sealing compound 22, the ends of the pole sections are sealed against infiltration of water and other foreign matter which would undesirably increase the weight of the pole sections, making it more diflicult to manually handle the loading pole in the shot hole.

The complementary coupling section 13 consists of an annular head 23 on which is formed parallel extensions 24 which are connected at their ends by an integral crossmem'ber 25 to form a loop defining the opening 26 which receives the hook 15 of the companion coupling member 12. The member 13 is also cast in a single piece and has a shank 30, provided with a cylindrical end portion 28 through which extends a transverse pin 29, the latter entering the Walls of the pole section 10 to hold the coupling against displacement from the end of the pole section. Aside from the head portions of the coupling members 12 and 13, they are identical in shape, the shank 30 being formed with radial ribs 31 to lighten the same in Weight, and an annular shoulder 32 which is equal in diameter to the shank 30 and end portion 28 to fit snugly in the opposite end of the pole section 10 which latter is sealed by a suitable sealing agent 33 to prevent infiltration of foreign matter which would add to the weight of the loading pole.

In Figure 7 is shown a modified form of the invention wherein the pole 40 is made of wood. The complementary coupling members 41 and 42 are similar in many respects to the corresponding coupling members described in' the foregoing. The coupling member 41 has a hook 43, provided with an opening 44 in one side thereof to accommodate the complementary coupling member 42. The body 41 has a tapered ferrule 45 which is adapted to receive one end of the pole 40 and is secured thereto by means of a transverse pin 46.

The coupling member 42 is formed with the parallel leg portions 47, connected by a transverse rib 48 whose diameter is slightly less than the width of the opening 44 of the hook 43 so that it can be received in the said opening only when the axes of the coupling members 41 and 42 are disposed at relative right angles, thus to prevent accidental displacement of the rib 48 from the hook 43. In the manner of the coupling member 41, the member 42 has a tapered ferrule 49 into which is received an end of an adjacent pole 40 and is held in secure relationship with the pole by a transverse pin 50. The tapered ends of the ferrules 45 and 49 allow the coupling members to slide freely through the hands of the workman whose duty it is to assemble and disassemble the pole sections.

In operation, an explosive sharge (not shown) is so a r r r 2,861,828 v r p m ,5

connected to the lower end of the first loading pole section that it can be readily shaken loose into the shot hole by vigorously shaking thestring of sections vertically. The pole sections are assembled as they are lowered into the hole ,by disposing the added pole sections at..-such an angle that one coupling member will engage witliits complementary vmember and so on until the explosive charge reaches the bottom of the hole. .pole section enters thehole, a detonating wire 34 is .connected to the charge and to asource of .electricalcurrent ,at the surface. After the charge is loosened into the hole, the pole sections. 10 are removed whereupon the charge may be detonated.

Manifestly, the construction as shown and vdescribedlis capable of some modification .and such modification as may be construed to fallwithin the scope and meaning of the appended claims is also considered to be within the spirit and intent of the invention.

What is claimed is:

1. In a shot hole loading pole, the combination of a plurality of elongated pole sections detachably connected end to end, each section comprising a tubular member having a first coupling memberand a second coupling member connected to opposite ends thereof, each of the coupling members having a shank portion received in the adjacent end of the tubular member and a head portion capable of being detachably connected to the adjacent coupling member of .an adjoining section, the head portions each having a shoulder formed thereon for engagement by the adjacent .end of the tubular member, the shank portions each having a cylindrical inner end connected to the head portion by a plurality of circumferentially spaced, tapered longitudinal ribs each extending radially outwardly from the longitudinal axis of the shank portion, the shank portions being secured in the tubular members by friction fit and being additionally secured therein by pins extending transversely through the respective cylindrical end portions and the adjacent walls of the tubular member, the head portion of the first coupling member having an arcuate hook formed on the end there- .of opposite the shoulder, the hook having a side opening therein, and the head portion of the second coupling member being formed with a bifurcated end portion opposite the shoulder and having a transverse bar connectingits outer extremities to thereby ,define an opening capable of receiving the hook of an adjacentcoupling member corresponding to the-first coupling member when the coupling members are disposedat right angles with respect to each other.

2. A shot hole-loading pole section comprising an elongated tubular member, a first coupling member having a head provided with an annular shoulder and a hook formed on thehead opposite the shoulder, the hook being in the form of an incomplete circleand defining an opening in one sidethereof, an elongated shank integral with the head andishoulder and disposed in one end of the tubular Before the first member, the shank being formed with radially extending ribs and a cylindrical end portion, a second coupling member having an integral head, an annular shoulder, a cylindrical end portion and ashank analogous to the first coupling member, the latter shank being received in the opposite end of the tubular member, parallel tapered leg portions formed integral with the head of the second coupling member, a bar .of substantially U shape in transverse section interconnecting the leg portions and intersecting the longitudinal axis of the shank and defining an opening, the bar being receivable in the side opening of the hook of an adjacent coupling member corresponding to the first coupling member when the shanks of the coupling members are disposed at right angles to each other, and a sealing compound joining the shoulders of the heads and the cylindrical end portions of the shanks to the tubular member to seal the tubular member against infiltration of foreign matter.

3. In. a shot hole loading pole section, an elongated tubular member, a first coupling member havingaahead and a shank, the shank being frictionally received in one end of the tubular member, a hook formed integrally on the head opposite the shank, a second coupling member having a head and a shank received in the opposite end of the tubular member, a pair of parallel legs formed on the head opposite the shank and a transverse integral bar interconnecting the legs and intersecting the longitudinal axis of the shank and defining an opening adapted to receive the book of an adjacent coupling member correspending tothe first coupling member when the coupling members are disposed at relative right angles.

4. The structure of claim 3, and asealing agent joining the coupling members to the tubular member at ,each end of their shanks to preclude ingress of Water and .other foreign matter into the tubular member.

;5. The structure of claim 3, the shanks each being formed .of radial, longitudinally coextensive ribs havi g cylindrical portions at each end of a diameter substantially equal to the inner diameter of the tubular member.

References Cited in the file of this patent UNITED STATES PATENTS 

